U.S. patent application number 15/271391 was filed with the patent office on 2017-04-13 for actuation device for a piston of a syringe.
This patent application is currently assigned to CTC Analytics AG. The applicant listed for this patent is CTC Analytics AG. Invention is credited to Roland KERNEN, Melchior ZUMBACH.
Application Number | 20170102403 15/271391 |
Document ID | / |
Family ID | 54325344 |
Filed Date | 2017-04-13 |
United States Patent
Application |
20170102403 |
Kind Code |
A1 |
ZUMBACH; Melchior ; et
al. |
April 13, 2017 |
ACTUATION DEVICE FOR A PISTON OF A SYRINGE
Abstract
The present application relates to an actuation device for a
piston of a syringe. The actuation device comprises a holder for a
barrel of the syringe, a coupling which is linearly movable
relative to the holder and has a seat into which the piston of the
syringe can be inserted, at least one securing element with which
the piston can be secured releasably in the seat, and a linear
drive for the coupling. The coupling has at least two electrically
conductive contact elements which are arranged inside the seat in
order to come into contact with corresponding electrically
conductive contact faces of the piston when the piston is inserted
into the seat. The present application further relates to a
sampling system with an actuation device and with at least one
syringe, and also to a syringe suitable for the sampling
system.
Inventors: |
ZUMBACH; Melchior;
(Lenzburg, CH) ; KERNEN; Roland; (Muttenz,
CH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CTC Analytics AG |
Zwingen |
|
CH |
|
|
Assignee: |
CTC Analytics AG
Zwingen
CH
|
Family ID: |
54325344 |
Appl. No.: |
15/271391 |
Filed: |
September 21, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G01N 35/1009 20130101;
B01L 3/022 20130101; B01L 3/0237 20130101; G01N 30/00 20130101;
B01L 2200/143 20130101; G01N 1/14 20130101; B01L 3/0224 20130101;
G01N 30/24 20130101; F04B 9/00 20130101; B01L 2300/024 20130101;
F04B 53/14 20130101; F04B 53/16 20130101; G01N 2001/1427 20130101;
F04B 19/22 20130101; B01L 3/0275 20130101 |
International
Class: |
G01N 35/10 20060101
G01N035/10; F04B 53/14 20060101 F04B053/14; F04B 19/22 20060101
F04B019/22; F04B 53/16 20060101 F04B053/16; G01N 1/14 20060101
G01N001/14; F04B 9/00 20060101 F04B009/00 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 9, 2015 |
EP |
15 189 183.5 |
Claims
1-14. canceled
15. An actuation device for a piston of a syringe, comprising a
holder for a barrel of the syringe, a coupling which is linearly
movable relative to the holder and has a seat into which the piston
of the syringe can be inserted, at least one securing element with
which the piston can be secured releasably in the seat, and a
linear drive for the coupling, wherein the coupling has at least
two electrically conductive contact elements which are arranged
inside the seat in order to come into contact with corresponding
electrically conductive contact faces of the piston when the piston
is inserted into the seat.
16. The actuation device according to claim 15, wherein an inner
wall of the seat is designed as a first contact element of the at
least two contact elements.
17. The actuation device according to claim 15, wherein a first
contact element of the at least two contact elements is designed as
a round face, and the at least one further contact element is
designed as a circle concentric to the round face.
18. The actuation device according to claim 15, wherein the at
least two contact elements are prestressed inside the seat, counter
to a direction of insertion of the piston, by at least a first
spring element.
19. The actuation device according to claim 15, wherein the at
least one securing element is designed as a form-fit element, which
can engage in a circumferential groove of the piston when the
piston is inserted into the seat.
20. The actuation device according to claim 19, wherein the
form-fit element comprises at least one ball which is placed in an
opening of the seat, wherein a sleeve is arranged on the outside of
the seat and is movable relative to the seat from a first position
to a second position such that, in the first position, the at least
one ball is pressed by the sleeve into an interior of the seat and,
in the second position, the at least one ball is movable out of the
interior.
21. The actuation device according to claim 15, wherein the linear
drive comprises at least one spindle.
22. The actuation device according to claim 15, wherein the at
least one securing element is designed in such a way that the
piston can be automatically secured in the seat and released
therefrom.
23. A sampling system comprising an actuation device according to
claim 15 and also at least one syringe with a barrel and with a
piston arranged partially inside the barrel and linearly
displaceable therein, wherein a non-volatile memory element is
arranged on an end of the piston not arranged inside the barrel,
and wherein the memory element is connected to at least two
electrically conductive contact faces which are shaped and arranged
on the barrel in such a way that they can come into contact with
the electrically conductive contact elements of the actuation
device when the piston is inserted into the seat.
24. The sampling system according to claim 23, wherein the
actuation device is connected to an electronic control system or
comprises the latter, wherein the electronic control system is
configured to read out data from the non-volatile memory element
and/or to write data into the latter.
25. The sampling system according to claim 24, wherein the data
contain at least one of the following items of information: number
of piston strokes executed, size of the barrel, serial number of
the syringe, production date of the syringe, total travel of the
executed piston strokes, manufacturer of the syringe, data of the
first executed piston stroke, size of the needle connected to the
barrel.
26. The sampling system according to claim 23, wherein the form-fit
element comprises at least one ball which is placed in an opening
of the seat, wherein a sleeve is arranged on the outside of the
seat and is movable relative to the seat from a first position to a
second position such that, in the first position, the at least one
ball is pressed by the sleeve into an interior of the seat and, in
the second position, the at least one ball is movable out of the
interior, wherein an outer circumferential surface of the piston of
the syringe has a circumferential groove in which the ball engages
when the sleeve is in the first position.
27. A syringe for a sampling system according to claim 23,
comprising a barrel and a piston arranged partially inside the
barrel and linearly displaceable therein, wherein a non-volatile
memory element is arranged on an end of the piston not arranged
inside the barrel, which memory element is connected to at least
two electrically conductive contact faces.
28. The syringe according to claim 27, wherein a first contact face
of the at least two contact faces is round, and the at least one
further contact face is designed as a circle concentric to the
round first contact face.
Description
TECHNICAL FIELD
[0001] The invention relates to an actuation device for a piston of
a syringe, in which electrical signals can be transmitted between
the syringe and the actuation device by means of contact elements
with contact faces located on the piston of the syringe. The
invention moreover relates to a sampling system with an actuation
device and with at least one syringe, and also to a syringe
suitable for this sampling system.
PRIOR ART
[0002] Actuation devices, for pistons of syringes, and sampling
systems have already been known for some time in the field of
laboratory equipment. Such devices and systems are in particular
used in the course of laboratory automation such that a large
number of samples can be prepared with a high degree of precision,
for example for subsequent chromatographic analysis. In such
pipetting procedures, it is desirable for the automatic systems and
devices to contain data relating to the syringe used, so as to
avoid any errors that may arise through the use of syringes that
are unsuitable or too old. Moreover, in the process of
documentation, in particular in the medical sector, it is
advantageous if, for example, it can be established without any
doubt which sample has been prepared with which syringe. Therefore,
some systems and devices are known in the prior art in which
information is exchanged between an actuation device or a sampling
system and a memory located on the syringe.
DISCLOSURE OF THE INVENTION
[0003] The object of the invention is to make available an
actuation device for a piston of a syringe, which actuation device
belongs to the technical field mentioned at the outset and, in the
simplest possible way, allows data exchange with a memory element
arranged on the syringe.
[0004] The object is achieved by the features of claim 1. According
to the invention, the actuation device has a holder for a barrel of
the syringe. Moreover, the actuation device comprises a coupling
which is linearly movable relative to the holder and has a seat
into which the piston of the syringe can be inserted, at least one
securing element with which the piston can be secured releasably in
the seat, and a linear drive for the coupling. The coupling has at
least two electrically conductive contact elements which are
arranged on an inner wall of the seat in order to come into contact
with corresponding electrically conductive contact faces of the
piston when the piston is inserted into the seat.
[0005] The at least one securing element of the coupling provides a
fixed mechanical connection between piston and coupling, as a
result of which a reliable contact between the electrically
conductive contact elements and the contact faces of the piston is
permitted. Data exchange between a memory element, arranged on the
piston of the syringe, and the actuation device can be achieved
without expensive electronic components such as transmitters or
receivers for wireless data transfer, and therefore the
manufacturing costs both of the actuation device and also of the
piston can be kept down. Moreover, by means of the electrical
contact, a memory element arranged on the piston can be supplied
with current, and therefore no additional source of current has to
be arranged in or on the piston.
[0006] The holder preferably has a securing device with which the
barrel of the syringe can be secured releasably thereto. The
securing device is preferably designed in such a way that the
barrel of the syringe is held with form-fit engagement in the
holder. The holder is preferably connected releasably to the
securing device. In order to use another syringe with the actuation
device, in this case the holder is replaced by a holder with the
required syringe. For the releasable connection of the holder to
the actuation device, these have corresponding holding means which
are in particular designed in such a way that an automatic exchange
of the holder, and therefore of the syringe placed in the holder,
can take place. A holder of this kind is described, for example, in
EP 2 261 676 B1 from the applicant. In this way, the actuation
device according to the invention can be used in a pipetting robot
with automatic syringe exchange.
[0007] The inner wall of the seat is preferably designed in such a
way that it defines an interior which substantially corresponds to
the outer shape of an end area of the piston, such that the piston
can be held inside the seat with the least possible play.
[0008] The at least one securing element is preferably designed in
such a way that it releasably secures the piston with force-fit
and/or form-fit engagement in the seat.
[0009] The coupling can be moved linearly relative to the holder by
means of the linear drive. Since the barrel of the syringe is
secured in the holder and the piston is secured in the coupling,
this relative movement between holder and coupling leads to a
linear movement of the piston inside the barrel. In this way,
liquids can be drawn into or ejected from the syringe.
[0010] A ram is preferably arranged inside the seat, with which ram
a piston located in the seat can be pushed out when released. In
particular, this ram is preferably prestressed by a spring element
in the direction of an opening through which the piston can be
inserted into the seat. Moreover, with this prestressing, a force
is exerted permanently on a piston located in the seat, as a result
of which it is possible to reduce any play in the axial direction
between piston and securing element. This permits more precise
guiding of the piston by the coupling.
[0011] It is particularly preferable that the at least two
electrically conductive contact elements are arranged on a side of
the ram that comes into contact with the piston when the piston is
inserted into the seat. The prestressing of the ram has the effect
that the at least two contact elements are pressed against the
piston, which greatly improves the mechanical contact of the
electrically conductive contact elements with the piston.
Alternatively, it is also possible for just one of the at least two
electrically conductive contact elements to be arranged on the ram.
In this case, the inner wall of the seat can form the second
contact element or can have at least one further contact
element.
[0012] Moreover, provision can also be made that the ram is formed
as a first of the at least two contact elements. In this
embodiment, the ram has to be produced from an electrically
conductive material.
[0013] In the context of the present application, "axial direction"
is understood as the direction in which the longitudinal axis of
the syringe and of the piston lies when the syringe is secured on
the actuation device. The linear displacement of the coupling
relative to the holder takes place along this axial direction.
[0014] It is particularly preferable that the actuation device is
arranged on an arm of a sampling system mounted displaceably in at
least one spatial axis. The sampling system is in particular
designed as a pipetting robot which automatic processing of liquid
samples, for example for automated chromatography procedures, in
particular liquid chromatography, mass spectrometry or gas
chromatography.
[0015] The inner wall of the coupling is preferably designed as a
first contact element of the at least two contact elements. For
this purpose, the inner wall of the seat is made from a conductive
material, for example copper or steel. The at least one further
electrically conductive contact element is electrically insulated
from the inner wall of the seat in this configuration. It is
particularly preferable in this embodiment that the inner wall
carries the reference potential and accordingly serves as mass for
a memory element arranged on the syringe.
[0016] Preferably, a first contact element of the at least two
contact elements is designed as a round face, and the at least one
further contact element is designed as a circle concentric to the
round face.
[0017] In this way, it is at all times possible to guarantee that
the contact faces located on the piston of the syringe are touched
by the contact elements without the piston having to adopt a
specific position with respect to the rotation about its
longitudinal axis. For example, it is thus possible, independently
of the rotation position of the piston, to produce an electrical
contact between contact faces, formed on the latter as pins, and
the contact elements. This simplifies the handling of the actuation
device.
[0018] Preferably, the at least two contact elements are
prestressed inside the seat, counter to a direction of insertion of
the piston, by a spring element. Preferably, the prestressing of
the at least two contact elements is effected via a common spring
element. Particularly preferably, a separate spring element is
provided for each of the at least two contact elements. It is thus
possible to ensure that the contact elements are at all times
pressed onto the contact faces of a syringe secured in the seat,
independently of any manufacturing tolerances.
[0019] The at least one securing element is preferably designed as
a form-fit element, which can engage in a circumferential groove of
the piston when the piston is inserted into the seat.
[0020] The form-fit element preferably comprises at least one ball
which is placed in an opening of the seat, wherein a sleeve is
arranged on the outside of the seat and is movable relative to the
seat from a first position to a second position such that, in the
first position, the at least one ball is pressed by the sleeve into
an interior of the seat and, in the second position, the at least
one ball is movable out of the interior.
[0021] This results in a securing element that has a very simple
design and is easy to operate. The ball preferably engages in a
groove surrounding the piston, in order to secure the piston in the
seat with form-fit engagement. In this way, the piston can at all
times be secured in the seat, without the piston first having to be
rotated to the correct position.
[0022] It is particularly preferable that the form-fit element
comprises three balls which are preferably arranged at an angle of
120.degree. relative to each other about the axial direction. In
this way, the form-fit element has the effect that the piston is
centred on the axial direction.
[0023] The sleeve is preferably prestressed into the first position
by a first spring element. The actuation device preferably has an
actuator with which the sleeve can be moved automatically from the
first position to the second position and back again. In this way,
a piston can be secured in the seat and released from the seat
without the intervention of operating personnel, as a result of
which the actuation device can be used in an automated pipetting
robot.
[0024] The opening, the ball and the sleeve are preferably designed
in such a way that the ball cannot fall out of the coupling.
[0025] The linear drive preferably comprises at least one spindle.
The use of a spindle permits very precise movement of the coupling,
and therefore of a syringe piston secured in the seat, and, when
the actuation device is used in a pipetting robot, this allows
precisely defined amounts of a liquid to be taken up or dispensed
by the syringe.
[0026] The at least one securing element is preferably designed in
such a way that the piston can be automatically secured in the seat
and released therefrom.
[0027] The present application further relates to a sampling system
with an actuation device according to the invention and with at
least one syringe. The syringe has a barrel and a piston arranged
partially inside the barrel and linearly displaceable therein,
wherein a non-volatile memory element is arranged on an end of the
piston not arranged inside the barrel. The memory element is
connected to at least two electrically conductive contact faces,
which are shaped and arranged on the barrel in such a way that they
can come into contact with the electrically conductive contact
elements of the actuation device when the piston is inserted into
the seat.
[0028] The actuation device is preferably connected to an
electronic control system or comprises an electronic control
system, wherein the electronic control system is for this purpose
configured to read out data from the non-volatile memory element
and/or to write data into the latter.
[0029] In this way, data can be retrieved from the memory element
prior to a sampling procedure, and, after a sampling procedure has
been carried out, data can be written onto the memory element or
data can be changed. In a fully automatic system in particular, it
is thus possible, for example, to check whether a syringe with the
correct volume is connected to the actuation device. Moreover, data
relating to the use of the syringe can be stored on the memory
element.
[0030] The electronic control system is preferably configured in
such a way that it permits automatic securing and release of the
syringe. That is to say, the electronic control system can control
motors with which the actuation device can be moved in at least one
spatial direction. Moreover, the linear drive of the actuation
device is also preferably connected to the electronic control
system and can be controlled by the latter.
[0031] Moreover, the electronic control system is also configured
in such a way that it can be connected via a connection to a
network in order to permit complete integration of the sampling
system in a production or analysis set-up and/or to permit data
exchange with further electronic appliances.
[0032] The data preferably contain at least one of the following
items of information: number of piston strokes executed, size of
the barrel, serial number of the syringe, production date of the
syringe, total travel of the executed piston strokes, manufacturer
of the syringe, data of the first executed piston stroke, size of
the needle connected to the barrel.
[0033] On the basis of these data, the electronic control system
can be used to check whether the syringe secured on the actuation
device is suitable for the intended sampling. On the one hand, the
transmitted data relating to the syringe can be compared directly
with the required properties for the planned sampling procedure. On
the other hand, the suitability of the syringe for the planned
sampling procedure can also be checked on the basis, for example,
of a serial number or batch number by comparison with a database
that is either stored in a memory of the electronic control system
or can be interrogated on a remote server via a network.
[0034] The form-fit element preferably comprises at least one ball
which is placed in an opening of the seat, wherein a sleeve is
arranged on the outside of the seat and is movable relative to the
seat from a first position to a second position such that, in the
first position, the at least one ball is pressed by the sleeve into
an interior of the seat and, in the second position, the at least
one ball is movable out of the interior. An outer circumferential
surface of the piston of the syringe has a circumferential groove
in which the ball engages when the sleeve is in the first
position.
[0035] A configuration of this kind allows the piston to be secured
in the seat in a way that is as simple as possible in mechanical
terms, and yet efficient. Since the ball can be brought into
engagement with the groove about the entire circumference of the
piston, the piston does not also have to be specifically oriented
in order to permit securing, and this greatly simplifies
handling.
[0036] Particularly preferably, the form-fit element comprises
three balls which are placed in corresponding openings of the seat.
The balls are in particular arranged at an angle of 120.degree.
relative to each other on the circumference of the seat. This
allows the piston to be centred.
[0037] The following application further relates to a syringe for a
sampling system according to the invention. The syringe comprises a
barrel and a piston arranged partially inside the barrel and
linearly displaceable therein, wherein a non-volatile memory
element is arranged on an end of the piston not arranged inside the
barrel, which memory element is connected to at least two
electrically conductive contact faces.
[0038] The electrically conductive contact faces are located on the
surface of the piston such that they can come into contact with the
corresponding contact elements of the seat when the piston is
placed in the seat of the actuation device.
[0039] The memory element is preferably let into the material of
the piston and is connected to the contact faces by electrical
leads. For example, the memory element, and lines leading to it and
connected to the contact faces, can be encapsulated by injection
moulding during the production of the piston. In this production
method, it is necessary to ensure that the memory element used does
not suffer damage at the temperatures during the injection
moulding.
[0040] A first contact face of the at least two contact faces is
preferably round, and the at least one further contact face is
preferably designed as a circle concentric to the round contact
face.
[0041] In this way, it is at all times possible to guarantee that
the contact elements inside the seat of the actuation device are
contacted without the piston having to adopt a specific position
with respect to the rotation about its longitudinal axis.
[0042] In the arrangement with more than two contact faces, these
contact faces, with the exception of the first round contact face,
are designed as circles that are spaced apart from each other and
that are concentric relative to each other.
[0043] The at least two contact faces are arranged on a base
surface of the piston lying at right angles to the axial
direction.
[0044] Alternatively, a first contact face can be designed as a
printed circuit board which is arranged on the circumferential
surface of the piston and which is in contact with the inner wall
of the seat when the piston is placed in the seat.
[0045] Further advantageous embodiments and combinations of
features of the invention will become clear from the following
detailed description and from all of the patent claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0046] In the drawings used to explain the illustrative
embodiment:
[0047] FIG. 1 shows a schematic view of a sampling system according
to the invention;
[0048] FIG. 2 shows a sectional view of the sampling system from
FIG. 1;
[0049] FIG. 3 shows a sectional view of the sampling system from
FIG. 2, with the syringe released from the actuation device;
[0050] FIG. 4 shows a more detailed view of a chip arrangement with
contact faces and memory element.
[0051] In principle, identical parts are provided with identical
reference signs in the figures.
WAYS OF IMPLEMENTING THE INVENTION
[0052] FIG. 1 shows a schematic view of a sampling system 1
according to the invention with an actuation device 2 to which a
syringe 3 is secured. The syringe 3 has a barrel 4 in which a
piston 5 is mounted in a linearly displaceable manner. Moreover, a
needle 6 is connected to the barrel 4 of the syringe 3, via which
needle 6 a liquid can be drawn in or ejected.
[0053] The actuation device 2 has a holder 7 for the barrel 4 of
the syringe 3, and a coupling 8 to which the piston 5 of the
syringe 3 is releasably connected. The coupling 8 is linearly
displaceable relative to the holder 7 by a linear drive 9. This
displacement has the effect that the piston 5 is also displaced
inside the barrel 4. The displacement path of the piston 5 inside
the barrel 4 of the syringe 3 takes place in the axial direction.
The axial direction is parallel to the longitudinal axis A of the
syringe 3.
[0054] The holder 7 is connected releasably to the actuation device
1 by holding means, such that the holder 7 can be removed and
exchanged along with the syringe 3 secured to it. Thus, the syringe
3 used with the actuation device 1 can be exchanged very quickly
and easily, since a new syringe 3 does not have to be secured on
the holder 4, and instead only the holder 4, which can be connected
to the actuation device 1 by holding means, is exchanged. Thus,
when exchanging the syringe 3, there is no need for the
time-consuming clamping, particularly when exchanging with a
syringe 3 having a greater or smaller barrel.
[0055] FIGS. 2 and 3 show sectional views of the sampling system
from FIG. 1. FIG. 2 shows the situation according to FIG. 1, in
which the syringe 3 is secured on the actuation device 2. FIG. 3
shows the situation when the syringe is released from the actuation
device 2.
[0056] The coupling 8 has a seat 11 into which an end of the piston
5 of the syringe 3 is insertable. The seat 11 has a circumferential
wall 10, which is secured on an arm 26. The arm 26 connects the
coupling 8 to the linear drive 9, with which the coupling can be
linearly displaced relative to the holder 7.
[0057] The piston 5 has a chip arrangement 19, which is shown in
somewhat greater detail in FIG. 4. The chip arrangement 19 has at
least two contact faces (see FIG. 4) which are in contact with two
contact elements 20, 21 which are arranged inside the seat 11 of
the coupling 8 when the piston 5 is inserted in the seat 11. The
contact elements 20, 21 are connected via cable 22 to an electronic
control system (not shown). When the contact faces of the chip
arrangement 19 are in contact with the contact elements 20, 21,
electrical signals can be exchanged between the chip arrangement 19
and the electronic control system, in particular in order to write
data in a memory element of the chip arrangement 19 or to read out
data therefrom.
[0058] The coupling 8 moreover has a sleeve 12 which is arranged on
the outside of the wall 10 of the seat 11 and is mounted linearly
displaceably with respect to the latter. The sleeve 12 is
prestressed to the shown first position by a first spring element
16. In this position, a ball 13 arranged in an opening 14 of the
seat 11 is pressed into the interior of the seat 11 and thus in the
direction of the piston 5. The piston 5 of the syringe 3 has a
circumferential groove 22 in which the ball 13 engages. In this
way, the piston 5 is secured with form-fit engagement in the seat
11.
[0059] As is shown in FIG. 3, the sleeve 12 can be moved away from
the syringe 3, counter to the spring force of the first spring
element 16, to a second position by means of an actuator 15. An
inner wall of the sleeve 12 is shaped in such a way that the ball
13 can be moved out from the interior of the seat 11 when the
sleeve 12 is located in the second position. In this way, the ball
13 can be released from the engagement with the circumferential
groove 22, whereupon the piston 5 is freed from the coupling 8.
[0060] A ram 18 is arranged inside the seat 11 and is prestressed,
by a second spring element 17, in the direction of the piston 5 or
in the direction of an opening of the seat 11 into which the piston
5 can be inserted. In the embodiment shown, the two contact
elements 20, 21 are arranged on this ram. In this way, they are
pressed together with the ram 18 onto the chip arrangement 19 by
the spring force of the second spring element 17, in particular
onto the contact faces of the chip arrangement 19 of the piston
5.
[0061] When the piston 5 is released by movement of the sleeve 12
to the second position, it is pushed out of the seat 11 by the
spring force of the second spring element 17 acting on the ram 18,
which simplifies the removal of the piston 5 from the seat.
[0062] FIG. 4 shows a more detailed view of the chip arrangement 19
according to the embodiment of the sampling device 1 from FIGS. 1
to 3. The chip arrangement has a memory element 25, which is
configured as a non-volatile memory. The memory element 25 stores
data relating to the syringe 3, for example its volume, the number
of executed piston strokes, etc. The memory element 25 is connected
to two contact faces 23, 24, which are located on the chip
arrangement. A first contact face 23 is designed as a round face. A
second contact face 24 is designed as a circular surface arranged
concentrically around the first round contact face 23. The first
contact face 23 and the second contact face 24 are spaced apart
from each other by an electrically insulating distance 27. The
contact faces 23, 24 are arranged on a plate 28, which is secured
on the memory element 25.
* * * * *